Bolt



*l y drawing wherein the outer e'dge of the Patented Jan. 17, 1933UNITED STATES ROBERT SAIBDESON,

PM'ENT ori-ICE OI' mNEAPOLIS, MINNESOTA, .ASSIGNOB TO LEWIS BOLT & IUT

CODANY, A CORPORATION OF MINNESOTA BOLT continuation of applicationSerial No. 474,444, filed August 11, 1930. This application med July 7,1988.

- Serial No. .$21,248.

The invention relates to bolts and particularly to bolts of the typeprovided with fins under the heads thereof.

This application is a continuation of my co-pending application, SerialNumber 474,- 444 filed August l1, 1930.

A preferred form of the invention .is embodied in a screw-threaded boltprovided with a relatively thin head adapted to be drawn into a woodenbeam throughwhich the bolt is passed, afnut being employed on thescrew-threaded shank of the bolt to draw the relatively thin head intothe wooden beam. The bolt is provided with integral triangular-shaped nsunderneath the head which fins are also drawn into the wooden beam. Oneside of each iin is disposedin a plane extending substantiall radiallyfrom the shank, the other side of t e fin being disposed at an acuteangle to said plane to provide a relatively shar cutting edge alongEril. This cuttmg edge facilitates the task of drawing the iin into thewooden beam. The radially extending surface of the fin prevents the boltfrom turning in a direction which will. cause it to unscrew itself fromthe nut threaded thereon.

Other advantages will become apparent as the following detaileddescription progresses, reference being had to the accompanying Figure 1is a perspective view of a bolt which embodies the invention.

Figure 2 is aside elevation of the improved bolt, the bolt being shownin connection with l a wooden beam through which it extends, and Figure3 is a section taken on line 3-3 of Fi re 1.

eferring to the drawing, the reference character 10 designates the shankof the improved bolt, the shank 10 being provided with screw threads atone end and an integral head 12 at its other end. Screw-threaded and theshank 10 are a plurality of fins 15. As indicated at 16 one side of eachin 16 is disposed in a plane extending substantially radially from thelongitudinall axis of the shank 10, the other side 17 of each nbeingdisposed at an acute angle to the correspondtightened until thedisc-like head 12 is drawn into the beam so that its outer surface isapproximately iush with the surface of the beam. When the nut istightened inA this manner, the fins 15 are drawn into the wooden beam isillustrated in Figures 2 and 3. 'The radiallyextending surfaces 16 ofthe fins 15 engage the wooden beam in such manner that they prevent thebolt from turning in a direction which will cause the nut 13 to beloosened on the bolt.

The improved bolt is particularly adaptable for railroad carconstruction and almost any industry where wood construction is afactor. A feature of the invention is that the head of the bolt issuiciently thin to be drawn substantially flush with the surface of thewood, the thin disc-like headbeing reenforced by the fins so that itdoes not fail when it is used in this manner. The cutting edges of thefins insurethat the fins and the disc-like head may be drawn into thewood.

,In some instances, the top surface of the improved bolt is machined toa plane surface. This accentuates the disc-like appearance of the head.

While I have shown and described certain embodiments of my` invention,it is to be understood that it is capable ofman modi- -iications.Changes, therefore in t e construction and arrangement may be madewithout departing from the spirit and scope o f the invention asdisclosed in the appended claim, in which it is my intention to claimall novelty inherent in my invention as broadly as possible, in view ofthe prior art.

I claim:

`A screw-threaded bolt comprising a thin disc-like head adapted to bedrawn into a. wooden beam through which the bolt is passed, and asubstantially triangularshaped fin integral with the shank and head ofsaid bolt and extending along the under side of said head from the shankto a point substantially at the periphery of said head, one side of saidfin being disposed in a plane extending substantially radially from saidshank, and the other side of said fin being disposed at an acute angleto said plane to provide a relatively sharp cutting edge along the outeredge of said fin whereby said fin may be forced readily into said woodenbeam, said radially extending surface of said fin being adapted toengage the Wooden beam A to prevent the bolt from turning in thedirection necessary to nnscreW it from a nut threaded thereon.

In witness whereof, I have hereunto subscribed my name this 21st da ofJune, 1932.

ROBERT ARDESON.

